The present invention relates to foot mats of the type that are widely used in and near the entryways of commercial, industrial, and institutional buildings to clean the footwear of persons entering the building and minimize the tracking of dirt and moisture into the building and are often used in various work areas.
One type of foot mat used for building entryways and work areas is composed of elongated, rigid rail members connected in a manner that allows the rails to articulate so that the mat can be rolled up. Examples of such mats, which are similar in concept but have various forms of connections between the rail members, are described and shown in the following United States patents:
U.S. Pat. No. 4,029,834 (Bartlett, 1977)xe2x80x94The rail members include a socket on one side and a flange with an enlarged bead of round cross section on the other side. The socket on each rail receives the bead on an adjacent rail. The bead rotates in the socket to enable adjacent rails to articulate.
U.S. Pat. No. Re. 32,061 (Ellingson, Jr., 1986)xe2x80x94The rail members have sockets on both sides, each of which receives an enlarged bead on a rigid connector of xe2x80x9cdogbonexe2x80x9d shape in cross section. The concept is essentially the same as that of Bartlett ""834, except that the rail members have sockets on both sides and the dogbone connector members are separate from the rail members.
U.S. Pat. No. 4,568,587 (Balzer, 1986)xe2x80x94Sockets in each side of the rail members receive enlarged heads on flexible xe2x80x9cIxe2x80x9d-shaped connectors, articulation being enabled by flexure of web portions of the connectors.
U.S. Pat. No. 4,654,245 (Balzer et al., 1987)xe2x80x94The design is essentially the same as Balzer ""587, except for the addition to the connectors of L-shaped feet, which underlie portions of the rail members and provide non-slip cushions under the mat.
U.S. Pat. No. 5,157,804 (Williams, 1992)xe2x80x94The rail members have beads on each side and are joined by connectors that have sockets that receive the beads. The rails are coextrusions of plastic and have a body of a rigid plastic and layers of soft plastic on the bottoms of supporting feet on the body.
U.S. Pat. No. 5,486,392 (Green, 1996)xe2x80x94The rail members have sockets on each side that open toward the floor and are joined by flexible plastic U-shaped connectors, each of which has an enlarged bead at the upper end of each leg that is received in a socket on the rail member. The connectors rest on the floor and serve as cushions and flex to allow the mat to be rolled up.
An affiliate of the assignee of the present invention, Constructions Specialties (UK) Ltd., markets a foot mat under the trademark PEDILUXE that has rail members with sockets that open along each side and receive enlarged beads on connectors. The sockets of the rail members of the PEDILUXE mats are located below the sides of a web portion. A tread member, such as a carpet strip, extends widthwise almost completely across the top of each rail member, leaving only a narrow flange of the rail member visible on either side of the tread member.
All of the mats referred to above are assembled by sliding the connecting beads lengthwise into the sockets along the entire length of the rail member from one end. The assembly process is laborious and time-consuming and requires a large work area. It is not uncommon for rail members of four meters (12 feet) in length to be assembled using separate connector members, also four meters (12 feet) long. Assembly in that manner also requires a sliding fit between the socket and bead, thus leaving some degree of laxity in all connections. After a desired number of rail members are connected to form the mat, some form of fastener arrangement is required between each rail member and the connector for that rail member to the adjacent rail member, whether the connector be a portion of the adjacent rail member (see Bartlett ""834) or a separate connector member (see, e.g., Ellingson, Jr.), to prevent the rail members from sliding longitudinally relative to each other.
Installation of the required fastener arrangement is yet another laborious, tedious and time-consuming operation. When both the socket and bead are of metal, there is a tendency for the mat to rattle due to the sliding fit and metal-to-metal contact. Except for the PEDILUXE mats, all of the mats referred to above have the coupling portions along the sides of the rail members, and the tread members, such as carpet strips, are set in from the side extremities. Thus, a significant portion of the total mat area is taken up by the side connector portions of the rail members. The exposed metal or plastic connector portions of the rail members or of connectors between the rail members are not universally pleasing in appearance to designers and architects.
One object of the present invention is to provide a foot mat of the type described above that is constructed in a manner that eliminates tedious and time-consuming assembly procedures. Another object is to provide a foot mat that can be readily varied in appearance and function without major modifications of the components or the fixtures and tools used for assembly. Still another object is to improve the appearance of foot mats that use rail members and connectors. It is also desired to retain many of the advantages of previously known designs, such as cushioning elements incorporated into connector members, the absence of metal-to-metal contact between relatively movable parts, the capability of being rolled up, and the capability of accepting different tread surfaces.
The foregoing objects are attained, in accordance with the present invention, by a foot mat that includes a plurality of substantially rigid elongated rail members arranged closely adjacent each other with a gap between each adjacent pair of rail members. Each rail member is of substantially uniform cross section along its length and includes a body portion having side edges, an upper surface and a lower surface and a pair of leg portions projecting generally downwardly from the lower surface of the web portion and spaced apart from each other and from the side edges of the web portion. An elongated tread member is received on the upper surface of the web portion of each rail member. A connector member joins each pair of adjacent rail members to each other, each connector member being an extrusion of at least one polymeric material and being of substantially uniform cross section along its length and including a connecting web portion extending across the gap between the adjacent rail members and a pair of generally U-shaped socket portions. Each socket portion defines a cavity that receives the leg portion of one of the adjacent rail members and is configured to be snap-fitted onto the rail members by pressing the socket portions onto the leg portions of the rail members. Each leg portion and each socket portion have interengaging shoulders configured to retain the leg portion in the socket portion.
The polymeric material of the socket portions should be sufficiently flexible to enable the socket portions to deform and accept the leg portions on the rail members by press-fitting but not so flexible as to permit the leg portions to be readily detached from the leg portions on the rail members. Snap-fitting the connector members onto the adjacent rails has the very important advantage of making assembly much easier to do and requiring significantly less time than sliding them on lengthwise. It is also possible for a complete mat to be partially assembled in sections at a factory and the sections shipped flat to the job site in stacks of a convenient size for handling. The sections can be joined at the job site by installing suitable connectors between the sections.
Providing the leg portions on the rail members and the socket portion on the connectors enhances the stiffness of each rail member and also provides supporting feet for each web portion, the bottom surfaces of the leg portions being located close to the floor on which the mat rests for stable support. The bottom surface of each leg portion can be of a width suitable to avoid high bearing stresses in the bases of the socket portions of the connector members, which is desirable when, as is highly preferred, the connector members are plastic.
An optional, but highly advantageous, feature of the present invention is the inclusion on each rail member of a pair of laterally spaced-apart, dependent elongated anchor tab portions, each of which engages a socket portion of one of the two connector members to which the rail member is coupled. Each of the anchor tab portions is plastically deformed when the mat is assembled and grips the socket portion so as to prevent longitudinal displacement of the rail member relative to the two connector members. The anchor tabs also clamp the socket portions of the connectors to the leg portions of the rails, thus preventing detachment of the leg portions of the rails from the socket portions of the connectors. Each of the anchor tab portions is, preferably, longitudinally coextensive with the body portion of the rail member. It is also desirable for each anchor tab portion to have a plurality of teeth on a contact surface that engages a socket portion of a connector. The teeth may penetrate a surface of the socket portion to attain a good grip. Instead of or in addition to having teeth on the anchor tab portions to enhance the gripping of the connectors to the rails, parts of the leg portions of the rails that are engaged by the socket portions of the connectors may have gripping teeth. Although other fastening arrangements are possible to hold the rail members and connector members against longitudinal displacements relative to each other, the anchor tab portions of the present invention greatly facilitate and speed up assembly, as compared to previously known fastening arrangements.
Each connector member may be an extrusion of a single polymeric material, such as polyvinyl chloride, having enough flexibility to allow snap-fitting of the socket portions onto the leg portions of the rails, permitting the mat to be rolled up, and providing cushioning under the leg portions of the rail members. Each connector may, to advantage, also be a co-extrusion of a relatively soft and flexible polymeric material and a relatively hard and semi-rigid polymeric material, the web portion being of the soft and flexible material and at least a portion of each socket portion being of the hard and semi-rigid material. Use of a hard material for the socket portions makes them more resistant to permitting the leg portions of the rails to pull out. The use of a soft flexible material for the web portion permits the adjacent rail members to articulate by flexure of the web portions, which allows the mat to be rolled up for a thorough cleaning of the floor below it. It is not, however, essential for the web portion to be flexible or for the mat to be capable of being rolled up, inasmuch as a rigid mat can be moved in a flat state from the floor on which it rests for cleaning of the floor. It is desirable, but also not essential, to have a layer of the soft polymeric material under the base of each socket portion to provide a cushion and impart slip resistance.
Each socket portion, in preferred embodiments of the mat of the present invention, has a base portion, an inner flange portion adjacent and joined to the web portion, and an outer flange portion, each of the inner and outer flange portions having a shoulder facing the base portion. Each leg portion of each rail member has an inner shoulder facing and engaging the shoulder on the inner flange portion of the socket and an outer shoulder facing and engaging the shoulder on the outer flange portion of the socket. Snap-fitting of the leg portions of the rail members into the socket portions of the connector members is facilitated by forming the shoulders on the flange portions of each socket as surfaces of protruding beads and providing on each bead a sloping cam surface that diverges from a juncture with the shoulder in a direction away from the base portion of the cavity. Each cam surface is engageable by a surface of the leg portion of the rail member for deformation of the socket portion to accept the leg portion by snap-fitting when the connector member is pressed onto the adjacent rail members upon assembly of the foot mat. Similarly and advantageously, each leg portion of each rail member has sloping cam surfaces converging from junctures with the shoulders on the leg portions in a direction away from the body portion of the rail member, each cam surface being engageable with the flange portions of the socket for deformation of the socket to accept the leg portion by snap-fitting when the connector member is pressed onto the adjacent rail members upon assembly of the foot mat.
It is also desirable for the web portion of the connector member to engage the undersides of parts of the body members of the rail members adjacent the gap between the rail members in order to avoid having any space between the web portion of the connector and the body portions of the rail members where dirt can collect. The web portion of the connector member may have holes to allow water and dirt to pass through to the floor under the mat.
Each rail member should have a side flange portion along each side of the body portion and a lip forming an inwardly facing groove to capture an edge portion of the tread member. As described below, various tread members can be used interchangeably with the same rail members.
As an optional feature for enhancing the good looks of the mat, a decorative cap of, for example, stainless steel or brass can be affixed to each side of the body portion of each rail member. The cap provides an accent strip that sets off each tread member visually. Each cap may have a lip that forms with a portion of the body portion of the rail member an inwardly facing groove that captures an edge portion of a tread member.
For a better understanding of the present invention, reference may be made to the following description of exemplary embodiments, taken in conjunction with the accompanying drawings.